The study was published in the Journal of the American College of Cardiology.
In the study, researchers found that individuals who slept less than six hours were 27 percent more likely to develop atherosclerosis. They also found that women who slept more than eight hours every night had an increased risk of plaque buildup – which causes the hardening of the arteries – throughout their body.
But it's not just the amount of sleep that a person gets that is linked to cardiovascular health.
The researchers also found that subjects who reported poor sleep quality were 34 percent more likely to have atherosclerosis than those who generally had a good night’s sleep. In addition, they drank more alcohol or caffeinated drinks.
These findings showed that sleep is independently linked to atherosclerosis all over the body, not just in the heart.
Dr. Jose M. Ordovas, one of the authors and a researcher at the Spanish National Center for Cardiovascular Research, says that in the early stages of the disease, plaque development occurs faster in the periphery of the body than in the heart.
He also says that when it comes to sleep, it is better to have a few hours of good sleep than to spend hours worrying that you won't get a restful sleep.
Ordovas hopes that future studies could look into the multi-territory assessment of atherosclerosis to accurately identify individuals at risk.
Lack of sleep is linked to an increase in risk factors for heart disease, such as high blood glucose levels, high blood pressure, inflammation, and obesity. (Related: Confirmed: Yet another study proves lack of exercise and poor sleep makes you FAT.)
Data has also linked sleep with other problems, such as:
For their study, Ordovas and his fellow researchers observed 3,974 Spanish volunteers who were then participating in a research to detect vascular lesions via imaging techniques. None of the participants had any history of heart disease and their average age was 46.
To gather data on their sleep patterns, they asked all of the volunteers to wear an actigraphy monitor for seven nights. The device monitored their activities and movements. They also asked the volunteers to undergo 3D heart ultrasound and cardiac CT scans for signs of heart disease.
The results suggested that short or poor sleep still contributed to atherosclerosis even after other risk factors were controlled.
Ordovas says that it could mean additional, unmeasured mechanisms increase the risk brought about by poor sleep quality. He recommends getting six to eight hours of sleep to maintain homeostasis of the circadian rhythm and expects future research to help people achieve "precision sleep."
Dr. Purvi J. Parwani, a cardiologist at the Loma Linda University International Heart Institute in California, noted that the relative health of the volunteers and the fact that the researchers measured sleep themselves instead of relying on self-reports make the findings "especially strong."
Parwani also said that while sleep is important, the study revealed that sleep may also be a risk factor for cardiovascular disease that is independent of all the other known factors.
The study confirms the importance of getting enough rest each night. Take care not to stay up too late but also avoid sleeping too much so you can stay healthy and lower your risk of heart disease.